This is revision 8 implementing a GPU crash state for drm/msm (https://patchwork.freedesktop.org/series/36097/). This patchset adds better documentation and reflects comments from the mailing lists. I know we will miss 4.19 at this point, but I think this is ready to soak in msm-next for a while.
The object of this code is to store and provide enough information to debug software and hardware issues on the Adreno hardware in a semi human-readable format that can also be parsed by scripts.
THe full set of changes here capture basic information about the GPU, the status and contents of the ringbuffers, a snapshot of the current register state and the active buffers from the hanging submit.
The data is printed with devcoredump. For example, after a hang you can get the data from /sys/class/devcoredump/devcdX/data where X is a unique number.
v8: Add documentation and consolidate puts/printf code from code comments v7: Add EXPORT_SYMBOL for __drm_puts_coredump and use %zd to print a size_t variable for the bo dump thanks to the ever vigilant zero one bot. v6: Add drm_puts() and use it in the appropriate place. Clean up a few minor bugs here and there. v5: Fix symbol error in i915_gpu_error.c thanks to 01 dot org bot. Added open/release functions for the show debugfs file to get the state per Chris Wilson. Slightly modified the register output format to be more YAML friendly also per Chris. v4: Add buffer dump for the active submit. Fix refcount issue with devcoredump. Change header for a5xx registers to registers-hlsq because I'm told YAML requires unique tags. v3: Make recommended changes to ascii85 per Chris Wilson. Use devcoredump to dump crash states as suggested by Bjorn Andersson and add a new drm_print facility to facilitate that. Remove the now obsolete 'crash' debugfs node. Add documentation for the crash dump output. v2: Convert output to yaml, use ascii85 to dump ringbuffer contents.
Jordan Crouse (13): include: Move ascii85 functions from i915 to linux/ascii85.h drm: drm_printer: Add printer for devcoredump drm: Add drm_puts() to complement drm_printf() drm: Add a -puts() function for the seq_file printer drm: Add puts callback for the coredump printer drm/msm/gpu: Capture the state of the GPU drm/msm/gpu: Convert the GPU show function to use the GPU state drm/msm/gpu: Rearrange the code that collects the task during a hang drm/msm/gpu: Capture the GPU state on a GPU hang drm/msm/adreno: Convert the show/crash file format drm/msm/adreno: Add ringbuffer data to the GPU state drm/msm/adreno: Add a5xx specific registers for the GPU state drm/msm/gpu: Add the buffer objects from the submit to the crash dump
Documentation/gpu/msm-crash-dump.rst | 96 ++++++++++ drivers/gpu/drm/drm_print.c | 111 +++++++++++ drivers/gpu/drm/i915/i915_gpu_error.c | 34 +--- drivers/gpu/drm/msm/Kconfig | 1 + drivers/gpu/drm/msm/adreno/a3xx_gpu.c | 30 +-- drivers/gpu/drm/msm/adreno/a4xx_gpu.c | 22 ++- drivers/gpu/drm/msm/adreno/a5xx_gpu.c | 242 ++++++++++++++++++++++-- drivers/gpu/drm/msm/adreno/adreno_gpu.c | 184 ++++++++++++++++-- drivers/gpu/drm/msm/adreno/adreno_gpu.h | 10 +- drivers/gpu/drm/msm/msm_debugfs.c | 93 ++++++++- drivers/gpu/drm/msm/msm_gpu.c | 145 +++++++++++++- drivers/gpu/drm/msm/msm_gpu.h | 68 ++++++- include/drm/drm_print.h | 71 +++++++ include/linux/ascii85.h | 38 ++++ 14 files changed, 1044 insertions(+), 101 deletions(-) create mode 100644 Documentation/gpu/msm-crash-dump.rst create mode 100644 include/linux/ascii85.h